When network coverage is restricted, a base station triggers a cell handover. An existing cell handover is triggered based on the downlink signal quality, that is, when the downlink signal quality is lower than a threshold, a user equipment (User Equipment, hereinafter briefly referred to as UE) is triggered to perform a cell handover. In a network plan, however, a phenomenon of imbalance between uplink power and downlink power exists. As a result, a situation where uplink coverage is restricted earlier than downlink coverage may occur. That is to say, when the downlink coverage is not restricted, the uplink coverage is already restricted. Particularly, in a scenario where interference exists in the uplink, the uplink transmit power of a UE is more probably restricted earlier than the downlink, thereby causing the uplink coverage to be restricted earlier than the downlink coverage. If the uplink transmit power of the UE is restricted, call drop is likely to occur.
A cell handover manner in the prior art has the following problems: a handover is triggered based on the downlink signal quality, and an uplink signal restriction situation cannot be accurately characterized. When uplink coverage is restricted earlier than downlink coverage, because the downlink signal quality does not reach a threshold that triggers a handover, a handover is not triggered, thereby causing a UE to be prone to call drop. Therefore, a method for detecting whether uplink power is restricted needs to be provided, so that a handover can be triggered when it is detected that uplink power is restricted.